| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.sqoop.mapreduce; |
| |
| import java.io.IOException; |
| import java.sql.Connection; |
| import java.sql.PreparedStatement; |
| import java.sql.SQLException; |
| import java.util.List; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.mapreduce.RecordWriter; |
| import org.apache.hadoop.mapreduce.TaskAttemptContext; |
| import org.apache.sqoop.lib.SqoopRecord; |
| |
| /** |
| * This class uses batch mode to execute underlying statements instead of |
| * using a single multirow insert statement as its superclass. |
| */ |
| public class ExportBatchOutputFormat<K extends SqoopRecord, V> |
| extends ExportOutputFormat<K, V> { |
| |
| private static final Log LOG = |
| LogFactory.getLog(ExportBatchOutputFormat.class); |
| |
| @Override |
| /** {@inheritDoc} */ |
| public RecordWriter<K, V> getRecordWriter(TaskAttemptContext context) |
| throws IOException { |
| try { |
| return new ExportBatchRecordWriter<K, V>(context); |
| } catch (Exception e) { |
| throw new IOException(e); |
| } |
| } |
| |
| /** |
| * RecordWriter to write the output to a row in a database table. |
| * The actual database updates are executed in a second thread. |
| */ |
| public class ExportBatchRecordWriter<K extends SqoopRecord, V> |
| extends ExportRecordWriter { |
| |
| public ExportBatchRecordWriter(TaskAttemptContext context) |
| throws ClassNotFoundException, SQLException { |
| super(context); |
| } |
| |
| @Override |
| /** {@inheritDoc} */ |
| protected boolean isBatchExec() { |
| // We use batches here. |
| return true; |
| } |
| |
| @Override |
| /** {@inheritDoc} */ |
| protected PreparedStatement getPreparedStatement( |
| List<SqoopRecord> userRecords) throws SQLException { |
| |
| PreparedStatement stmt = null; |
| |
| // Synchronize on connection to ensure this does not conflict |
| // with the operations in the update thread. |
| Connection conn = getConnection(); |
| synchronized (conn) { |
| stmt = conn.prepareStatement(getInsertStatement(userRecords.size())); |
| } |
| |
| // Inject the record parameters into the VALUES clauses. |
| for (SqoopRecord record : userRecords) { |
| record.write(stmt, 0); |
| stmt.addBatch(); |
| } |
| |
| return stmt; |
| } |
| |
| /** |
| * @return an INSERT statement. |
| */ |
| protected String getInsertStatement(int numRows) { |
| StringBuilder sb = new StringBuilder(); |
| |
| sb.append("INSERT INTO " + tableName + " "); |
| |
| int numSlots; |
| if (this.columnNames != null) { |
| numSlots = this.columnNames.length; |
| |
| sb.append("("); |
| boolean first = true; |
| for (String col : columnNames) { |
| if (!first) { |
| sb.append(", "); |
| } |
| |
| sb.append(col); |
| first = false; |
| } |
| |
| sb.append(") "); |
| } else { |
| numSlots = this.columnCount; // set if columnNames is null. |
| } |
| |
| sb.append("VALUES "); |
| |
| // generates the (?, ?, ?...). |
| sb.append("("); |
| for (int i = 0; i < numSlots; i++) { |
| if (i != 0) { |
| sb.append(", "); |
| } |
| |
| sb.append("?"); |
| } |
| sb.append(")"); |
| |
| return sb.toString(); |
| } |
| } |
| } |